Steam power producing plant working with two water sources, the difference of temperature of which is small



April 29, 1952 Y L. NISOLLE STEAM POWER PRODUCING PLANT WORKING WITH TWO WATER SOURCES, THE DIFFERENCE 0F TEMPERATURE OF WHICH IS SMALL 6 Sheets-Sheet 1 Filed April 18, 1946 April 29, 1952 L. NISOLLE 2,595,164

STEAM POWER PRODUCING PLANT WORKING WITH TWO WATER SOURCES, THE DIFFERENCE OF TEMPERATURE OF WHICH IS SMALL Filed April 18, 1946 6 Sheets-Sheet 2 mWwf/ April 29, 1952 so 2,595,164

STEAM POWER PRODUCING PLANT WORKING WITH TWO WATER SOURCES, THE DIFFERENCE OF TEMPERATURE OF WHICH IS SMALL 6 Sheets-Sheet 3 Filed April 18, 1946 smmvww April 29, 1952 Nl$0LLE. 2,595,164

STEAM POWER PRODUCING PLANT WORKING WITH TWO WATER SOURCES, THE DIFFERENCE OF TEMPERATUBE'OF WHICH IS SMALL FiledApril 18, 1946 6 Sheets-Sheet 4 i Fig. 5A

' IN VE N TOR Lon Nisalle BY WMfi 1 w ms A romvsrs April 29, 1952' NISQLLE 2,595,164

STEAM POWER PRODUCING PLANT WORKING WITH Two WATER SOURCES, THE DIFFERENCE 0F TEMPERATURE OF WHICH IS SMALL Filed April 18 1946 6 Sheets-Sheet 5 J4 I Y 42 4? E ,1: -J, k 1-? \{I 5 6)" g i g l i J, 9.;-

' I 1 5 E 1 16/ S i a a g Apnl 29, 1952 NISOLLE 2,595,164

STEAM POWER PRODUCING PLANT WORKING WITH TWO WATER SOURCES, THE DIFFERENCE OF TEMPERATURE OF WHICH IS SMALL Filed April 18, 1946 e Sheets-Sheet e Patented Apr. 29, 1952 STEAM POWER PROD ING WITH TWO DIFFERENCE OF WHICH IS SMALL Lon Nisolle, Paris, Fran National de la Rech UCING PLANT WORK- WATER SOURCES, THE TEMPERATURE OF ce, assignor to Centre erche Scientifique, Paris,

France, a corporation of France Application April 18, 1946, Serial No. 663,040

" In France March 24, 1943 Section 1, Public Law 690, August 8, 1946 Pat n ex 2.4,. 1 6.3

(01, zen-:2)

l8. Gleims- 1 19 .1% already P62 nm d t O e P Q producing devices, more particularly turbines, by means of oceansteamfi -i. e. steam produced through evaporation of warm water taken in the vicinity of the suriace of the seas, preferably in tropical regions, said steam being condensed by means of cold water taken in the deeper strata of the same sea.

Tn such a case the necessary installations for evaporating the water, condensing the steam and circulating'the water as well as the steam take up a considerable space owing to the large volumes of water and steam which must be moved. Furthermore, the necessity of maintaining a high vacuum in the whole of the enormous rooms in which the evaporation, the power production and the condensation are achieved makes the installation of the vacuum pumps difficult and gives rise to problems concerning the tightness and the resistance of the rooms to pressure, the solution of which is very difiicult.

The present invention relates to such an installation working between two sources of water the temperatures of which are both rather low and near to one another, said installation being accordingly able to use the difference of temperature between the surface and the deeper strata of the sea. Said installation makes it possible to provide in a relatively small space, the various above mentioned apparatus and piping and thus to do away with most of the pressure losses which, in the present case, have a great influence on the power yield of the installation.

According to the present invention, the installation comprises an outer casing shaped approximately as a hollow tore with a vert cal -axis, inside which are placedthe steam generators and condensers as well as the steam and water circulation piping, degassing devices for the incoming water, the steam distribution p ping and the blades of one or several turbine wheels having the same axis as the casing.

The said outer casing may be, for instance, partially or wholly made of re nforced concrete. It may further be made of metal.

Owing to the compact disposit on of the device andthe double curva ure of the casing walls, the latter can resist, without being very thick, outer pressures around 1 ka/cm and the production and maintenance of the vacuum inside the device are greatly facilitated.

The distribution piping supplying steam to the turbine blades is preferably movable, so as to allow an easy assembly and disassembly of the wheel. In such a case, it is advantageous to 2 build them out oi metal, in the form of a rigid assembly which can be taken out as "a single piece, said assembly being for instance introduced into a cylindrical recess, having the s ame axis as the casing and provided at'the upper part of the said casing.

To feed the installation with warm and cold water, pumps supplying the water and pumps evacuating it are placed for instance around the casing. The object of the said double set of pumps for each water circuit is to avoid the energy losses which would certainly take place when the tide varies the level of the sea. If one considers for instance the warm water circuit, the level and pressure of the water arriving on the evaporting surfaces should be constant while the level where the said water is taken in the sea and the level where it is thrown back are variable. Accordingly, while the total pressure necessary for circulating the water is constant, it is constantly dividedin a different manner between the incoming circuit and the outlet circuit. By c ploying in each part of the circuit a pump yielding a manometric pressure which can be regulated, either by its rotation speed or by the orientation of its blades (if it is a screw pump), one may at each moment regulate the pressure to the strictly necessary value. If on the contrary one single pump had to fulfill the two functions, the regulation of the output could be achieved only by providing in the incoming and outlet piping valves which, acting by regulating the flow, would create a loss of pressure which must be compensated by the. single pump.

With two pumps or two groups of pumps, the total of the manometric pressures yielded stays substantially constant and is equal to the total of the pressure losses which cannot be avoided and which would exist even if the level of the sea remained constant.

The casing of the installation being particularly apt to constitute by itself the outer wall of the whole power plant, it is advantageous in such a case to protect it against solar radiation, for instance by paints spread in zones having different absorbing powers according to the orientation with respect to the direction of sun rays. The object of such a disposition is to ensure a. substantial constancy of temperature all along the said surface, notwithstanding the daily variations of the solar radiation, due to the very great flow of water circulating along the said walls, this water having a temperature which is constant or only slightly variable with time.

The whole tore-shaped casing rests on a base,

partitions 1.

for instance through the medium of posts a certain number of which may be mounted on rollers so as to allow dilatation, said posts leaving between them openings and free passages for the service gangs and the mechanical elements which are to take their place in the center of the casing.

The annexed drawings show an example of an installation according to the invention. In the said drawings:

Fig. 1 is an elevational outer view of the said installation;

Fig. 2 is a plan view with partial section through line II-II of Fig. 4;

Fig. 3 is a half sectional view through line III-IIl'. of Fig. 2, at a greater scale;

Fig. 4 is a half sectional view similar to the preceding one through line IV-IV of Fig. 2;

Figs. 5A, 5B, 5C and 5D are partial sections taken respectively on lines VA-VA, VB--VB,

VC-VC and VD-VD of Fig. 3;

Fig. 6 is part of a sectional view through line series of posts 3 and 4, the outer posts 4 being mounted on rollers 4a so as to allow the free dilatation of the casing. The upper part of the latter is provided with reinforcing ribs 6.

The casing is internally divided into twelve sectors or compartments by means of separating The said compartments are connected with the exterior through piping the detail of which will be given hereafter.

The upper part of casing I nearest to the axis is hollowed out to form a cylindrical recess 3 1 inside which is placed a removable body formed by conduits 9, l and II concentrically placed and radially partitioned, braced by a beam l2.

On the top of casing rests a circular lid |3 supporting a generator l4 and from the lid is suspended a shaft carrying a horizontal turbine wheel |6 the blades ll of which are concentrically partitioned so as to form three rings corresponding to conduits 9, I0 and II. Wheel I6 is placed at the bottom of the cylindrical recess 8.

A double inverted dome l8 made of reinforced concrete ensures the rigidity of the whole casing I.

Each compartment of easing formed by partitions I is internally fitted in the following way:

At the end of conduits 9, I0 and II are three pipes I9, and 2| which end above a conical surface ,22 slightly sloped from a horizontal plane, sloping downwardly towards the outside of the casing. Said conical surface 22 is divided, by partitions 23 and 24 which form the pipes I9,

20 and 2| and by adjustable metallic valves 25 and 26 which extend below the partitions, into .three communicating parts forming the evapora- ..tors, 21, 2B and 29. The separating partitions I are interrupted on the level of the evaporators so that the latter form a continuous ring on the whole periphery of easing In four of the compartments, situated on two perpendicular diameters, the water from evaporator 29 flows out, .over a slight weir 30, into a pipe 3| extending down along the outer wall of the casing I and leading to the exterior through a pipe 32. The latter is connected, with interposition of an elastic joint 33, with a screw pump 34 (see Fig. 6).

Immediately below the evaporators is a series of boxes 35 communicating with one another at their extremity nearest to the axis of casing At the said extremity, the boxes are connected to the lower part of a ring 35 the height of which is greater than its breath and which runs around the whole casing I and is formed, in its upper part, into a bell-shaped tank 31. The outer wall of ring 35 ends in its upper part in a series of blades 38 leaving between them very small intervals. The bell-shaped tank 31 is connected, through a siphon 39, with evaporator 21.

On the other hand, for four of the compartments formed by the partitions 1 in the casing, diametrically opposite to one another and placed sideby side two by two, the box 35 is connected with a pipe 40 (see Fig. 7) going down along the outer wall of the casing and opening outside through a pipe 4|. The latter is connected by a tight joint 33, to a screw pump 42. Director blades 43 may be placed at the connecting point between boxes 35 and pipes 40.

Below boxes 35 is a free space 44 in which is provided a pipe 45 formed of two half-rings joined at their diametrically opposite extremities to pass out into pipe 46 occupying a similar position to that of pipes 3| or 40 and communicating with the exterior through pipes 41 connected by a tight joint 33, with a screw pump 48 (see Fig. 4) Director blades such as 43 may also be provided.

Pipe 45 (see Fig. 8) is connected, through openings 49 closed by perforated plates, with a ring 50 the height of which is greater than its breath and the lower part of which dips into a siphon 5| which supports a horizontal perforated plate 52 braced by reinforced concrete joints, the said plate forming the upper wall of a condenser 53. The bottom of the latter consists of a concrete slab 54 perforated with holes 55 regularly spaced for instance on three concentric circles centered on the axis of the casing. The holes are extended downwards by short tubes 55 which extend nearly down to the plate 52 which forms the upper wall of a condenser 51 similar to the preceding condenser, followed in its turn with another condenser 58 provided with a simple perforated bottom 53.

The three condensers 58, 51 and 53 are connected through apertures 60, 5| and 62, to three radial superposed pipes 65, 64 and 53 (see Fig. 9), connected in their turn with pipes 66, 51 and 68 connected respectively with the above mentioned conduits H, H] and 9. The upper pipe 63 connected to the lower condenser 58 is divided in two parts so as to pass downward on both sides of pipes 64 and 65. In the same way, the lower pipe 55 connected to the upper condenser 53 is extended beyond the extremities of pipes 63 and 64 and then rises toward condenser 53.

The lower part of the casing, situated under the condensers, forms an annular collector 69 connected through two pipes 10 placed diametrically opposite one another to two centrifugal screw pumps 1|.

In the space 44 are also provided four annular conduits or air collectors 12, I3, I4 and 15, respectively connected, through vertical pipes 16, with the four stages of two air extraction pumps T! and 18 placed in the empty part provided in the center of the installation and one of which 2s and 15.

isarspare pump. Pipe: 191a connects the tour c.01-

lectors with the; de-gassing device 11.. Pipes. 1-8, 88 and 8liconnect the collectors with the three condensers;

The extracted air from the airecollectors ill- 75 which-communicate with the warm water dcgassing bell 31 and with the condensers 53, 51 and58, is. tially treed from the-accompanying with. respect tohe bot om. terrace I]: "or the condenser, are numerous enou h terthe water level which establishes itself in the said "tubes; and which shows the difierenc oi pressures between condenser 53. and he: i ll wins com denser 51 toremain inside the tubes: not. to

comeabovethe'bottom-of the condenser-'35. This vapor by refrigerators 16a, in order to decrease the necessary power for the air-extraction pumps "and 1-8 Refrigerators are preferably located in compartments 82 where no pipe'IB passes.

The installation works as follows: The warm water, at a temperature of say 3.0"

0., taken {in the vicinity of the surface. or the sea, is forced by the four pumps .52 ?('see Figs. 5

and '7') into pipes and thercirom in o he boxes 35; '2 It, then passes into ring 188 and ov'er flows into th'e bell-shaped tank 31, passing be tween blades 38 which divide it into thin-sheets: In such ai state of division, it is de-gassed'undei a-vacuumyi'of about-0.150 createdby the firststage of say pump 11, connected with through pipelli, conduit'n andpi-pe Ha. The thif sde-gassed water is then "sent into hell a evaporator '21 through the siphon 39 forming a "The nonevaporated-warm water, which formsexcept for W -the totality of the distributed water,-flows over weirs 30 (see Fig. 6.) tand is discharged ;through pipes 3| and 32 'and'warm wat er extraction pumps 84.

The three steam flows, having different ternperatures and pressures, are evacuated through pipes ISL-20 and 2| "and are brought, through distribution'frings '9, l0 and II, into the three blade rings ll, of wheel 16, where they expand respectively to"' pressures corresponding for instance to 1'9, 16and13 C. At the outlet of blades I1, the steam flowsare broughtrespectively through conduits 66, filaand '68 then 63, 64 and 85 to condensers. 58, '51 andj53 into which they enter by the lateral openings 60, 6| and 62. The extraction pump 1'! creates inside the condensers, through vertical pipe's'lfi, annular pipes 13, I4 and 15 and pipes 19, 80i-and '81,, vacuums corresponding for instance respectively tofj19, '16'and 13C.

"On the other hand the cold water, taken from the deeper strata of the sea, for instance at a temperature of 8-10 C.. is forced by pumps 48 (see Fig: 4) into pipes 46 and annular pipes (see Fig. 8). Therefrom it flows, throughperforated j'plates 49, to the de-gassing bell 50 maintained under vacuum by the air extraction pump 11' in a similar manner to de-gassing device 31. After, having been de-gassed, the cold water passes through siphon 5] and spreads on plates 52 through which it flows into the firstcondenser 58 in which has been created the highest condensation vacuum. The said water encounters the? steam coming from pipes 65 and condcnses it, then it is collected in the lower part and flows out through openings of slab 54.

Tubes 56, the total cross-section of which is ensures that the abnormal pressure differences which may take place between the icondensersis manifestedonlybyistrong variations-of the level inside the communication tubes 56, without. any visible variation of the Water level on the periorated plates of the condenser 58, which en- "sures a substantially constant. flow of water.

The water-from condenser 53 then flows onto the plate 52 formin th iupp wall otcondeu'ser .51 and the perforations of which are calcu so that the Water level :abovethe-said -.plate" is maintained at adepth:ofrabouti20cm. It, on

"streams into condenser F57, condenses-the teem present in said condenser "and then hows the same way into condenser.

At the lower-part of easing ;l,,-it he water coming out of condenser 58 at. a temperatureof say-313 C; is collected incollector 89 .andis removed irom the latter by pumps "H .(see 3).

The turbine wheel .16 drives the generator H which is the source of directlyusable power. A part-of the power thus producedby'the generator is used for driving the variousauxiliary devices: air extraction pumps 11 and 18, water circulating pumps 34, 42, 48 and 11, air cooling pumps and pumps for bringing to theinstallation- 'thewsea' water 'takeni-rom the deeper strata of -the sea.

It should be noted that theywarm water circulating pumps are in a greater number-than-those' for circulating the cold water. :In view of the small quantity of watch-evaporated in each eve porator, the volume o1', warmwater which istto be circulated is about-three times greater than that of the cold Water.

As an example, an installation producing 14,1500 kw., 5,500 of which are used for moving the auxiliary devices, working at the above mentioned temperatures necessitates the use of eight warm water circulation pumps'having'reach "and-output of 10:5m5ls. and of four cold water circulation pumps'having only an output each of '7 mfi/s.

The volume of steam is approximately 13,500 m. /s. The diameter of the turbine wheel is then about 14 m.

The outer walls of easing l may be protected in any known manner against solar radiation and the inner walls may be heat insulated at those parts which are in contact with the-cold waterpi. e. corresponding to pipes 46 and collector 69, so as to avoid-uneoual dilatations 01' said casing, such dilatations entailing-possible cracks and air inlets. 1 4

What'I claim is:

l. A steam power producing plant capable of working between two-#sources of water, one a hot source and the other a cold source, the difference of temperatures of which is very small and in which the work steam is produced from the hot source in steam generators, said steam being condensed after expansion by means of the water of the cold source, the said plant comprising on the one hand an outer continuous and tight casing shaped approximately as a hollow tore with a vertical axis, a shaft coaxial with said casing, a turbine wheel on said shaft having peripheral blades arranged in the central part of said casing, a unit formed by successive steam generators and condensers wholly in said formed with casing, inlet" piping in said casing for leading the water from the hot source to said steam generators and the water from the cold sourceto said condensers respectively, discharge piping from the condensers, and piping for leading the work steam from said generators to said turbine blades and from said blades to said condensers, and on .the other hand peripheral pumps arranged around the toric casing and connected with the inlet and outlet piping for the cold and warm water.

2. A steam power producing plant capable of working between two sources of water. one a hot source and the other a cold source, the difference of temperatures of which is very small and in which-the work steam is produced from the hot source in steam generators, said steam being condensed after expansion by means of the water of'the'cold source, the said plantcomprising an outer continuous and tight casing shaped approximately as a hollow tore with a vertical axis, means tightly closing the upper part and the lower part of the free space provided in the axial "part of said toric casing, journal means fast with said means, a shaft coaxial with said casing and rotatively supported by said journal means, a turbine wheel on said shaft having peripheral blades arranged in the central part of said casing, a unit formed by successive steam generators and condensers wholly. in said casing, inlet piping in said'casing for leading the water from the hot source to said steam generators and the water from the cold source to said condensers respectively, discharge piping from the condensers, and piping for leading the work steam from said generators to said turbine blades and from said -blades to said condensers, and on the other hand peripheral pumps arranged around the toric casing and connected with the inlet and outlet pipingfor the cold and warm water.

3. A plant according to claim 2, in which the upper part of the casing nearest to the axis is a cylindrical recess, and a removable ring unit formed of the piping for leading the steam from the generators to the turbine blades closely fitting in said recess.

4-. 'A plant according to claim 2 in which water de-gassing devicesare inserted in the inlet piping leadfrom the hot water source to the steam generators andin the piping leading from the cold water source to the condensers.

5. A plant according to claim 2, in which the toxic casing rests on a base by means of posts leaving between one another a sufllcient free space to allow a free access under said casing.

6. A plant according to claim 2, in which the steam generators are formed of evaporators. 7. A plant according to claim 2, in which the means tightly closing the free space provided in the axial part of the toric casing'are respectively in its upper part and in its lower part a tight lidforming structure and a continuous air-tight wall.

8. A plant according to claim 6, in which the evaporators are constituted by substantially conical surfaces on which the hot feed water streams down in spread layers;

9. A plant according to claim 6, in which the evaporators'are constituted by a unit of vertical piping open in their upper part over the top of which the warm feed water flows and then streamsdown on their outside walls.

10. A plant according to claim 7, in which the tight lid-forming structure is a metallic one.

11. A plant'according to claim 2, in which the range of. temperatures between the two working sources is comprised between about and C 12. A plant according to claim 2, in which the temperatures of the cold and hot working sources are of the order of 5 to 10 C. and to C.

respecti-vely.

13. A plant according to claim 6, in which-the evaporators comprise water fountain devices in which the warm water feed springs up through small vertical openings.

14. A plant according to claim 6, in which the evaporator-s are constituted by boxes having perforated ceilings through which the warm feed water streams down like a shower.

15. A plant according to claim 2, in which the condensers are jet condensers. v

16. A plant according to claim 2, in which the condensers are jet condensers and constituted by boxes having perforated ceilings through which the water streams down'in a shower.

17. A plant according to claim 6, in which the evaporators are arranged in the upperpart .of the casing and the condensers in the lower part, the inlet piping for the warm and cold water being located between the evaporators and the condensers and the lower part of the casing forming a collector for the water which has been used for the condensation.

18. A plant according-to claim 6, in which an electric generator is mounted on the lid, the rotor of which is'connected with the shaft coaxial with the toric casing. 2 LEON NISOLLE."

REFERENCES CITED The following references are of record in" the file of this patent:

UNITED STATES PATENTS Hiittner Mar. 30, 1937 

